Fixed runtime type resolution.

graphene/types/interface.py

@@ -34,9 +34,7 @@ class InterfaceMeta(AbstractTypeMeta):
 
 
 class Interface(six.with_metaclass(InterfaceMeta)):
-    @classmethod
-    def resolve_type(cls, root, args, info):
-        return type(root)
+    resolve_type = None
 
     def __init__(self, *args, **kwargs):
         raise Exception("An Interface cannot be intitialized")

graphene/types/objecttype.py

@@ -17,7 +17,8 @@ class ObjectTypeMeta(AbstractTypeMeta):
         if not is_base_type(bases, ObjectTypeMeta):
             return type.__new__(cls, name, bases, attrs)
 
-        options = Options(
+        _meta = attrs.pop('_meta', None)
+        options = _meta or Options(
             attrs.pop('Meta', None),
             name=name,
             description=attrs.get('__doc__'),
@@ -49,8 +50,10 @@ class ObjectTypeMeta(AbstractTypeMeta):
 
 
 class ObjectType(six.with_metaclass(ObjectTypeMeta)):
-
-    is_type_of = None
+    @classmethod
+    def is_type_of(cls, root, context, info):
+        if isinstance(root, cls):
+            return True
 
     def __init__(self, *args, **kwargs):
         # ObjectType acting as container

graphene/types/typemap.py

@@ -139,12 +139,15 @@ class TypeMap(GraphQLTypeMap):
     @classmethod
     def construct_interface(cls, map, type):
         from .definitions import GrapheneInterfaceType
+        _resolve_type = None
+        if type.resolve_type:
+            _resolve_type = partial(resolve_type, type.resolve_type, map)
         map[type._meta.name] = GrapheneInterfaceType(
             graphene_type=type,
             name=type._meta.name,
             description=type._meta.description,
             fields=None,
-            resolve_type=partial(resolve_type, type.resolve_type, map),
+            resolve_type=_resolve_type,
         )
         map[type._meta.name]._fields = cls.construct_fields_for_type(map, type)
         # cls.reducer(map, map[type._meta.name])
@@ -165,6 +168,9 @@ class TypeMap(GraphQLTypeMap):
     @classmethod
     def construct_union(cls, map, type):
         from .definitions import GrapheneUnionType
+        _resolve_type = None
+        if type.resolve_type:
+            _resolve_type = partial(resolve_type, type.resolve_type, map)
         types = []
         for i in type._meta.types:
             map = cls.construct_objecttype(map, i)
@@ -173,7 +179,7 @@ class TypeMap(GraphQLTypeMap):
             graphene_type=type,
             name=type._meta.name,
             types=types,
-            resolve_type=type.resolve_type,
+            resolve_type=_resolve_type,
         )
         map[type._meta.name].types = types
         return map

graphene/types/union.py

@@ -31,8 +31,7 @@ class UnionMeta(type):
 
 
 class Union(six.with_metaclass(UnionMeta)):
-    def resolve_type(self, _type):
-        return type(_type)
+    resolve_type = None
 
     def __init__(self, *args, **kwargs):
         raise Exception("An Union cannot be intitialized")